1. Field of the Invention
The present invention relates to a pharmaceutical composition, and, in particular, to an antitussive agent containing Cynanchi Atrati extract as an active antitussive component and the method for making the same.
2. Description of the Related Art
It should be noted that reference is made herein to concepts and practices well known within the established realm of traditional Chinese herbal remedy. A brief notation regarding the pertinent aspects of the art appears in Appendix A.
Cynanchi Atrati Radix is the root and rhizome of Cynanchum atratum Bunge or C. versicolor Bunge, family Asclepiadaceae, which is known as Bai Wei (rendered herein in accordance with pinyin standards of Chinese Romanization) in traditional Chinese medicine.
Crude drugs of Cynanchi Atrati Radix used in Chinese medicine are generally horse's tail-shaped, 10-15 cm long with rhizome stout, tubercular, transversely growing and circular stem tracing at the upper part with numerous slender roots clustered in the lower regions, The root of Cynanchi Atrati is 0.1-0.2 cm in diameter, grey-yellow and fragile. Crude drugs of Cynanchi Atrati Radix are conventionally prepared as bitter and salty segments, characterized within the parameters of traditional Chinese herbal remedies as being cold in nature and attributive to stomach and liver channels.
In traditional Chinese medicine, Cynanchi Atrati Radix is known as a successful remedy for lower asthenic fever. Specifically, Cynanchi Atrati Radix is regarded as curative for seasonal febrile disease involving depleted yin levels with prolonged fever or high fever at night subsiding in the morning, infantile summer fever, postpartum fever, and so on. Traditional indications for Cynanchi Atrati Radix disperse the disruptive factors from the body surface, for common cold with prolonged fever, especially those with yin-deficiency. Promote diuresis and relieve stranguria of heat type and when complicated by hematuria.
In addition, Cynanchi Atrati Radix is prescribed conventionally in combination with Cortex Lycii Radicts or di gu pi (rendered herein in accordance with pinyin standards of Chinese Romanization) or Herba Artemisiae Annuae in Chinese herbal medicine.